1. Field of the Invention
The invention is directed to a pipeline with threaded pipes and a sleeve connecting the same, which is hung in a drill hole for transporting a liquid and/or a gaseous medium. An electrically driven pump or compressor is arranged at the front of the pipeline near the base of the drill hole and electricity is supplied to the motor of the pump/compressor by a cable hung in the drill hole.
2. Description of the Prior Art
In transporting crude oil or natural gas or mixtures of the two, it is conventional and known to arrange a turbopump or a turbocompressor at the start of a transporting pipeline in the region of the drilling base when the bearing pressure is too weak or for the purpose of increasing the transported quantity (EP 0480501). This turbopump or turbocompressor can be driven hydraulically by means of supplied liquid or electrically. When an electric motor is used as the drive means, the electric power must be fed to the electric motor via a cable. The clear cross section of the transporting pipe offers an obvious possibility for hanging the cable, especially since the axis of the turbodevice is aligned with the axis of the transporting pipeline. Nevertheless, because of the anticipated abrasion, for example, the cable is hung for technical reasons relating to safety and flow properties in such a way that it is situated in the annular space between the concentrically arranged transporting pipeline and the pipeline casing or liner. This annular space, which is already narrow in modern slim-hole drill holes which are becoming increasingly common, is extremely constricted in the region of the connecting sleeves, so that it is not possible to realize the desired large cable cross section and low power losses. Moreover, there is naturally a much higher risk in the narrow region of the connections that the cable will be damaged by contacting or knocking against the inner wall of the pipe liner. Since the drill holes have a depth of at least several hundred meters, generally more than 2000 m, there is a risk of fouling, and thus highly loading, the cable when installing the pipeline. In unfavorable cases the cable can even tear or the insulation can be damaged.